1884.] Professor J. W. Jiidd on KraJcatoa, 85 



WEEKLY EVENING MEETING, 



Friday, May 2, 1884. 



The Duke of Nobthumbebland, D.C.L. LL.D. President, 

 in the Chair. 



PfiOFESSOK J. W. JuDD, F.R.S. Scc, G.S. 



Krakatoa. 



The great subterranean convulsions which during the last few- 

 years have visited Croatia, Ischia, and Asia Minor, culminated in 

 the autumn of 1883 in the grand volcanic outburst of Krakatoa, the 

 most terrible and destructive event of its kind which has occurred 

 within the memory of the present generation. It is not, however, true, 

 as has been asserted, that this manifestation of volcanic energy was 

 of altogether unparalleled magnitude or of unprecedented character ; 

 for within the last 120 years at least two paroxysmal volcanic out- 

 bursts on an equally grand scale have occurred in the same district — 

 those namely of Papandayang in 1772, and of Tomboro in 1815. 



Situated as it is in the middle of the Sunda Strait, one of the great 

 highways of commerce, Krakatoa has been the subject of more exact 

 observation — before, during, and since the eruption — than was possible 

 in the case of any other volcano in equally violent activity. In spite 

 of this, however, the first accounts brought to Europe concerning the 

 great outburst were singularly inaccurate, and we are only now 

 beginning to glean from the vast mass of conflicting reports the true 

 story of the terrible event. Certain it was, however, that on the 26th 

 and 27th of August, 1883, the shores of Java and Sumatra were swept 

 by a great sea-wave which desolated considerable tracts of country and 

 destroyed the lives of more than 35,000 human beings, and that this 

 sea-wave was one of the most striking accompaniments of a paroxysmal 

 outburst of Krakatoa. 



The volcano of Krakatoa lies at the intersection of two great 

 fissures — indicated by numerous volcanic vents — in that part of 

 the earth's crust where we have the most abundant indication of 

 subterranean energy. The group of four small islands in the midst 

 of the Sunda Strait was evidently the " basal-wreck " of a grand 

 volcanic cone, which had been destroyed by a paroxysmal outburst in 

 prehistoric times. It is not improbable that the subsidence accom- 

 panying this great outburst gave rise to the depression which forms the 

 strait now separating Java and Sumatra. About 200 years ago the 

 volcano is known to have been in eruption for a period of eighteen 

 months, but since that time it has remained perfectly dormant. 



During the last few years numerous earthquakes have indicated 



